LEWISVILLE (CBSDFW.COM) – The dam at Lake Lewisville is in urgent need of repair. That’s according to the agency that built it — the U.S. Army Corps of Engineers.

The agency has planned a public meeting, Tuesday night, to discuss their concerns.

For 58 years the Lewisville dam has held back the waters of Lake Lewisville… all 23,000 acres of it.

Windsurfer Bruce Moore knows the area well. “This is a great spot,” he said.

As far as holding back the water, not too many people ever consider what would happen if one day the dam didn’t. “If it blows we got big trouble,” Moore said of the possibility.

The U.S. Army Corps of Engineers found failure isn’t out of the realm of possibility. In fact, a report in 2008 labeled the dam “very high risk” and in “urgent” need of repair. Another report this past December outlined its “potential to pose a significant risk to human life.”

The possible risks seem more than plausible, especially since the entire city of Dallas is just downstream from it. Lauren Fagerholm, a dam safety project manager for the Corps, admits there is a serious level of concern. “The level of risk identified is not acceptable to the Corps.”

Fagerholm went on to explain that both what’s seen and unseen are important. “A lot of things are below the surface that are hard to see. We have a lot of monitoring instrumentation in place to tell us what’s happening beneath that soil.”

Officials with the Corps said they not only looked at the likelihood the dam would fail, but also at the consequences that would follow. Leaders in the namesake city of the dam are also considering the unthinkable. “If something were to happen, it would affect so many people,” James Kunke, the Lewisville Director of Community Relations and Tourism, thought aloud.

The City of Lewisville would be the first to take the hit but the Corps says even Dallas would flood. “It’s reassuring to the city to see the Corps taking steps trying to make sure it doesn’t,” Kunke said.

The Corps is still in the early stages of planning but estimates a permanent fix would cost somewhere between $100 and $200 million.

Officials with the corps said their review of dams nationwide found that roughly 300 of the nation’s 705 structures are in need of repair.

Tuesday night’s meeting in Lewisville is being held at the Grand Theater and begins at 6:30 p.m.